   (let [red   (color/rgb 1 0 0)  ; hue 0/3
         green (color/rgb 0 1 0)  ; hue 1/3
         blue  (color/rgb 0 0 1)] ; hue 2/3
+    (quil/background 0)
+    (quil/stroke 0)
+
     ; red, green, and blue blocks
     (quil/with-translation [20 20]
       (quil/fill (color/gray 0.75))

      (quil/rect 50 10 40 40)
      (quil/fill (color/blend-hsv 0.5 blue red))
      (quil/rect 100 10 40 40)))
  )



      :title "Wonderdome Color Harness"
      :setup setup-harness
      :draw render-harness
      :size [650 400])))
